OBJECTIVE To investigate urogenital mycoplasma infection and its drug sensitivity in Beijing from Jul 2002 to Jun 2005. METHODS Mycoplasma were isolated and their antibiotic susceptibility was detected with Mycoplasma IST 2 Reagent Box from France. RESULTS Among 1806 cases 673 cases were with positive mycoplasma,accounting for 37.3% of the total.From them,Ureaplasma urealyticum(Uu) was positive in 541 cases(80.4%),higher than Uu combined with Mycoplasma hominis(Mh) infection(107 cases,15.9%) or Mh alone infection(25 cases,3.7%).The result of drug sensitivity test showed that Uu,Mh and Uu+Mh isolated from both sexes had different drug resistance.The most sensitive and stable antibiotics were josamycin(the rate of sensitivity was 98.7%) and pristinamycin(the rate of sensitivity 92.6%),the next was doxycyline(the rate of sensitivity was 91.8%).It seemed increasing sensitivity trend for tetracycline and erythromycin.The lowest rate of sensitivity was to ofloxacin and ciprofloxacin. CONCLUSIONS It is important to enhance the detection of drug resistance of mycoplasma,guide the drug use and prevent from producing antibiotic resistance.If antibiotic susceptibility testing of mycoplasma can not be tested,josamycin may be selected as the first choice to treat mycoplasma infection.

Objective To investigate the effects of NB-UVB on the expression of Gadd45α as well as cell apoptosis and cycle of human HaCaT keratinocytes.Methods Cultured HaCaT cells were exposed to various doses (100,200,400 mJ/cm2)of NB-UVB followed by an additional culture of 6,12 and 24 hours,respectively.Reverse transcription PCR and Western blot were performed to detect the mRNA and protein expression of Gadd45α respectively in HaCaT cells,cell counting kit 8 (CCK8)to measure the proliferation of cells,and flow cytometry to determine the cell cycle distribution of HaCaT cells before and after the exposure to NB-UVB.Results Gadd45α was expressed in HaCaT cells.After exposure to NB-UVB of the three doses,the mRNA and protein levels of Gadd45α increased at 6 hours and 12 hours,but declined at 24 hours,and significant changes were observed in HaCaT cells at the three time points after exposure to NB-UVB of the three doses (all P<0.05).The Gadd45α/β-actin mRNA ratio was 1.4360±0.6551.1.8633±0.0979,1.9266±0.1724 in HaCaT cells 12 hours after irradiation to NB-UVB of 100,200 and 400 mJ/cm2,respectively,significantly higher than that in unirradiated cells(0.6000±0.1276,all P<0.05).Also,increased Gadd45α/β-actin protein ratio was noted in HaCaT cells 12 hours after irradiation to NB-UVB of 100,200 and 400 mJ/cm2 compared with unirradiated cells (0.0773±0.0005,0.1936±0.0015,0.2373±0.0015 vs.0.0290±0.0010,all P<0.05).NB-UVB inhibited the proliferation of HaCaT cells in a time-and dose-dependent manner.Flow cytometry showed that irradiated HaCaT cells were blocked in G2 phase of the cell cycle.and the percentage of HaCaT cells in G2 phase was 13.53%±1.03%,17.77%±2.25%,30.03%±4.29%afler exposure to NB-UVB of 100,200 and 400 mJ/cm2,respectively,compared to 9.24%±0.97%in unirradiated cells (all P<0.05).Conclusions The expression of Gadd45α is increased in HaCaT cells after exposure to NB-UVB,and Gadd45α may be involved in the NB-UVB-induced suprression of cell proliferation of and cell cycle arrest in HaCaT cells.

Objective To compare the efficacy for aged patients with locally advanced esophageal cancer who accepted 3D-CRT with or without S-1.Methods 62 aged patients with locally advanced esophageal cancer were randomized divided into three groups in Central Hospital of Kaifeng since March,2009.The S-1 combined with radiotherapy group was 26 patients as combined group,the single radiotherapy group was 20 patients and single drug group was 16 patients.S-1 combined group patients accepted 3D-CRT,and the patients were taken S-1 from the first day,the dose was 40 mg/m2 twice a day continually 14 days and then stop 7 days.There were 2 cycles during radiotherapy.The 20 patients accepted 3D-CRT in single radiotherapy group,and the patients in single drug group were taken S-1 only,the dose was 40 mg/m2 twice a day continually 28 days and then stop 14 days within 28 days.Results The response rate was 92.31％ in S-1 combined group,with 13 patients CR,11 patients PR,and 1 patient SD.The response rate was 60.00 ％ in single radiotherapy group,with 4 patients CR,8 patients PR and 6 patients SD.The response rate was 31.25 ％ in single drug group,with 1 patients CR,4 patients PR and 6 patients SD.The effect of the S-1 combined with radiotherapy group was significant better than the others (P ＜ 0.05).The 1,2 and 3 year survival rates in each group were 76.92 ％,57.69 ％,42.31％,75.00 ％,55.00 ％,40.00 ％ and 68.75 ％,50.00 ％,25.00 ％,which there is no significant difference in the three groups.The adverse reaction of hematologic toxicity in S-1 combined with radiotherapy group was little higher than the others,still there was no significant difference in the incidence rate of radiation esophagitis and radiation pneumonitis between S-1 combined with radiotherapy group and single radiotherapy group.Conclusion S-1 plus three dimensional conformal radiotherapy treatments were reliable,and the adverse reactions were mild and well tolerated for elderly patients with locally advanced esophageal cancer.

Objective To investigate the effect of microRNA-let-7a on apoptosis in melanoma cell line A375 and its mechanism. Methods The expression of microRNA-let-7a was detected in A375 cells and melanocytes by real-time PCR. Then, microRNA-let-7a mimics was transfected into A375 cells followed by the measurement of apoptosis and caspase-3 protein expression by flow cytometry and Western blotting, respectively. Results The expression level of microRNA-let-7a was reduced by 0.462 folds in A375 cells compared with melanocytes. The apoptosis rate was 47.4% in A375 cells transfected with microRNA-let-7a mimics, significantly higher than that in untransfected A375 cells (16.9%). A significant decline was observed in the expression of caspase-3 protein in A375 cells after transfection. Conclusion microRNA-let-7a can promote the apoptosis and downregulate caspase-3 protein expression, in A375 human malignant melanoma cells.

Objective To investigate the treatment values of precise target delineation of chest MRI for lung cancer Methods From August 2011 to February 2015 , 45 non-small cell lung cancer patients were given chest CT scans and MRI scans before radiotherapy , and then active target tumor delineation , then related influencing factors were analyzed. Results All patients completed CT scans and MRI positioning. For patients that it was difficult to identify lung tissue lesions caused by lung cancer through CT , their MRI imaging showed high signal and the boundaries between the tumor and surrounding normal tissue became relatively clear. Meanwhile , 20 patients of borders were diagnosed by CT , while 25 by MRI; 36 patients with lymph node metastasis were diagnosed by CT while 40 by MRI. The difference was statistically significant (P<0.05). Univariate logistic regression analysis showed that pathological type and atelectasis were the influence factors for CT and MRI tumor target delineation differences (P<0.05), and multivariate logistic regression analysis showed the atelectasis was the main factor (P<0.05). Conclusion Compared with CT, breast MRI can precisely delineate target to improve the accuracy of target localization before radiotherapy. It can help determine lymph node metastasis and avoid the impact of atelectasis then ensure the accuracy of radiotherapy.

Objective To investigate the effect of MRE11 on the proliferation and apoptosis of esophageal squamous cancer cells and its molecular mechanism. Methods MRE11 expression was downregulated by MRE11 siRNA transfection in esophageal squamous cancer cells. The AKT agonist SC79 (0, 0.1, 0.5, 1, 1.5, 1.8, 2 μg/ml) were used to treat cells with MRE11 inhibition for 24 h. Overexpression vector pcDNA.3.1-c-myc was constructed and co-transfected cells with MRE11 siRNA. Western blot method was used to detect the protein expressions of MRE11, p-AKT and c-myc in esophageal squamous cancer cells Ec9706 and TE-1. The Annexin-V FITC/PI kit was used to detect the apoptosis of Ec9706 and TE-1 cells; the activity of caspase-3 was detected by the Caspase-3 activity detection kit; the proliferation of Ec9706 and TE-1 cells was tested by the BrdU method. Results The protein expressions of MRE11 in Ec9706 and TE-1 cells were significantly increased, compared with human esophageal epithelial Het-1A cells. After MRE11 siRNA transfection, AKT phosphorylation and the protein expressions of MRE11 and c-myc were significantly decreased in esophageal squamous cancer cells. MRE11 inhibition significantly promoted the apoptosis and caspase-3 activity in Ec9706 and TE-1 cells, while inhibited the proliferation of Ec9706 and TE-1 cells. SC79 (1.5, 1.8 and 2 μg/ml) significantly increased AKT phosphorylation in MRE11-suppressed esophageal squamous cancer cells, and reversed the inhibitory effects of MRE11 inhibition on c-myc protein expression and cell proliferation and the promoting effect on cell apoptosis. Overexpression of c-myc inhibited the inhibitory effect of MRE11 down-regulation on cell proliferation and the promotion on caspase-3 activity. Conclusion MRE11 inhibition could effectively inhibit the proliferation of esophageal squamous cancer cells and promote cell apoptosis by regulating AKT and c-myc.

Objective:To evaluate the effects of different density rat fibroblasts on the expression of conjunctin 43 (Cx43) in cardiomyocytes and cell viability.Methods:Cardiomyocytes and fibroblasts were co-cultured using Transwell, cardiomyocytes were inoculated into the lower chamber of Transwell and fibroblasts into the upper chamber of Transwell.The cells were divided into 3 groups ( n=12 each) by a random number table method: fibroblast density 0.5×10 5 cells/ml group (group C 0.5), fibroblast density 1×10 5 cells/ml group (group C 1), and fibroblast density 2×10 5 cells/ml group (group C 2), with the density of cardiomyocytes 1×10 5 cells/ml in three groups.Cardiomyocytes and fibroblasts were co-cultured for 20 h in three groups.Cardiomyocytes were collected after co-culture for determination of cell viability (by CCK8 method), apoptosis rate (by flow cytometry), and expression of Cx43 mRNA (by quantitative real-time polymerase chain reaction) and expression of Cx43 and phosphorylated Cx43 (p-Cx43) (by Western blot). Results:There was no significant difference in the apoptosis rate of cardiomyocytes among the three groups ( P>0.05). Compared with group C 0.5, the expression of Cx43 protein and mRNA and p-Cx43 was significantly up-regulated in group C 1, the cardiomyocyte viability was significantly increased, and the expression of Cx43 protein and mRNA and p-Cx43 was up-regulated in group C 2 ( P<0.05). Compared with group C 1, the cardiomyocyte viability was significantly increased, and the expression of Cx43 protein and mRNA and p-Cx43 was up-regulated in group C 2 ( P<0.05). Conclusion:Rat fibroblasts up-regulate the expression of Cx43 and enhance the activity of Cx43 in cardiomyocytes and enhance cell viability in a density-dependent manner in a certain range.

Objective:To evaluate the effects of different densities of rat cardiac fibroblasts (RCF) subjected to hypothermic hypoxia-reoxygenation on cardiomyocyte injury and intercellular coupling.Methods:RCF was cultured in vitro and divided into 3 groups ( n=12 each) using a random number table method: RCF density 0.5×10 5 cells/ml group (T 0.5 group), RCF density 1.0×10 5 cells/ml group (T 1.0 group), and RCF density 2.0×10 5 cells/ml group (T 2.0 group). The three groups were placed in an anoxic device, into which 95% N 2 + 5% CO 2 was continuously blown at the speed of 5 L/min for 15 min, and then placed in a 4 ℃ refrigerator for 1 h for low temperature treatment.After completion of culture, cells were placed in a incubator containing 95% air + 5% CO 2 at 37 ℃ for 4 h of reoxygenation.After the end of culture, RCF in three groups were indirectly co-cultured with cardiomyocytes of the same density (1.0×10 5 cells/ml) in a Transwell chamber for 16 h, cardiomyocytes were seeded in the lower chamber of Transwell, and RCF were seeded in the upper chamber of Transwell.After the end of co-culture, cardiomyocytes were collected for determination of the cell viability (by CCK8 method), apoptosis rate (by flow cytometry), expression of connexin 43 (Cx43) mRNA (by real-time fluorescence quantitative polymerase chain reaction), and expression of Cx43 and phosphorylated Cx43 (p-Cx43) (by Western blot). Results:Compared with T 0.5 group, the cell viability, apoptosis rate and expression of Cx43, p-Cx43 and Cx43 mRNA were significantly decreased in T 1.0 and T 2.0 groups ( P<0.01). Compared with T 1.0 group, the cell viability, apoptosis rate and expression of Cx43 and p-Cx43 were significantly decreased ( P<0.01), and no significant change was found in expression of Cx43 mRNA in cardiomyocytes in T 2.0 group ( P>0.05). Conclusions:RCF subjected to hypothermic hypoxia-reoxygenation induces cardiomyocyte injury in a density-dependent manner in a certain range, and the mechanism may be related to down-regulation of the expression of Cx43 and reduction of the activity of Cx43.